You will generally list your contributions to O.T.O. on Schedule A of your Form 1040 under “Charitable Contributions”. You will not need to send in receipts or other documentation to the IRS unless you are audited. But it is always a good idea to keep records backing up your deductions, for at least six years after the year when your return was filed.

Here are the records you should keep for each type of contribution:

• Dues – A receipt from your local body (or a letter from Grand Lodge if you sent in your national dues directly) showing the date and amount of your payment is fine.
• Donations – For small cash donations, such as jar donations at Mass, it is not necessary to have a receipt, but it’s a good idea to keep a written record. For larger donations, be sure to get a receipt.
   
  If your donation is $250 or more, you should get a letter from your local body indicating the date, amount of the donation, and a statement that the body is tax-exempt and no goods or services were provided to you in exchange for the contribution. A sample letter is available here.
• Expenses – Keep a copy of your receipts. For large purchases, have your local body write you a letter acknowledging receipt of the item. The letter will identify the item donated but won’t put a value on it — that’s what your receipt is for. A sample letter is available here.
• Mileage – Keep a log book in your car (they can be purchased at any office supply store) and record the beginning and ending mileage of each trip to and from your local body, and any other OTO event or location you drive on OTO business.
• Travel – Keep your receipts for airfare (a printout of your itinerary which includes the price paid for the ticket is fine), ground transportation, parking, lodging, and meals. Also, you should obtain a letter from your local body indicating that you attended the event (giving the location and dates of the event) as a representative of your local body.